Weed seed destruction

ABSTRACT

Weed seeds are destroyed in the chaff from a combine harvester by repeated high speed impacts caused by a rotor which accelerates the discarded seeds in a direction centrifugally away from the rotor onto a stator including angularly adjustable stator surfaces around the axis. Thus the discarded seeds rebound back and forth between the rotor and the stator to provide a plurality of impacts. The destructor is mounted on or coaxially with a suitable drive shaft in the straw stream such as the chopper rotor shaft. The rotor is mounted on bearings relative to the chopper rotor drive shaft and is coupled thereto by a releasable coupling between plates radial to the shaft so that the rotor can be stopped while the chopper rotor continues to operate in the event of a fault in the weed seed destructor.

This application is a continuation in part application of Application16/817190 filed March 12^(th) 2020 which claims the benefit ofProvisional Application 62/818417 filed March 14^(th) 2019, thedisclosures if which are incorporated herein by reference.

This invention relates to a weed seed destructor which can be attachedto a combine harvester so that weed seeds in the discharged chaff can bedevitalized before being spread onto the ground.

BACKGROUND OF THE INVENTION

In US Pat. 10,004,176 published Jun. 26, 2018 and US Publication2018/0070534 published Mar. 15, 2018 discloses an arrangement in whichweed seeds are destroyed in the chaff from a combine harvester by arotary mill causing repeated high speed impacts by a rotor mounted inone of a pair of side by side housings which accelerate the discardedseeds in a direction centrifugally away from the rotor onto a statorincluding angularly adjustable stator surfaces around the axis. Thus thediscarded seeds rebound back and forth between the rotor and the statorto provide a plurality of impacts. The angle of the discharge around therotor axis can be changed to direct the seeds to the side of the combineaway from a straw chopper, towards the guide fins of the tailboard ofthe chopper, or into the housing of the straw chopper.

SUMMARY OF THE INVENTION

According to the invention there is provided a combine harvestercomprising:

-   a separation system including a threshing system which separates    harvested crop into a first material stream comprising straw and a    second material stream comprising chaff and weed seeds;-   a rotary member mounted on the combine harvester for rotation about    a rotary axis;-   wherein the rotary member carries a plurality of straw engaging    members engaging the straw in the first material stream;-   and at least one weed seed destructor section comprising:    -   an inlet receiving the chaff and weed seeds in the second        material stream;    -   a first rotor having first rotor surfaces engaging the chaff and        weed seeds in the second material stream;    -   the first rotor being mounted for rotation about a rotor axis of        said at least one weed seed destructor section;    -   second stator surfaces engaging the chaff and weed seeds in the        second material stream;    -   the first rotor being mounted so that said rotation of the first        rotor relative to the second stator surfaces causing the chaff        and weed seeds to be impacted between said first rotor and        second stator surfaces so that the weed seeds in the second        material are devitalized before being spread onto the ground;-   wherein the rotor axis of said at least one weed seed destructor    section is coaxial with the rotary axis of the rotary member for    rotation about a common axis;-   wherein the rotor of said at least one weed seed destructor section    is connected by one or more connecting elements to the rotary member    for common rotation about the common axis;-   and wherein said one or more connecting elements are releasable to    allow the rotor of said at least one weed seed destructor section to    remain stationary while the rotary member rotates about the common    axis.

Preferably the rotary member includes a shaft component along the commonaxis and wherein the rotor of said at least one weed seed destructorsection is mounted on the shaft component.

Preferably the rotor of said at least one weed seed destructor sectionis mounted on the shaft component by a bearing to allow the shaft torotate with the rotary member while the rotor of said at least one weedseed destructor section remains stationary.

Preferably the rotary member includes a plate member lying in a radialplane of the common axis at the rotor of said at least one weed seeddestructor section and wherein the rotor of said at least one weed seeddestructor section is fastened to the plate member by said connectingelements.

Preferably the connecting elements comprise axially extending releasablescrew fasteners passing through a portion of the rotor of said at leastone weed seed

The arrangement herein thus provides a rotor for the weed seeddestructor section (WSD) rotor which is mounted on the chopping rotorshaft with bearings so that driver bolts can be taken out to disconnectthe drive from the chopping rotor to the WSD rotor. This can be usedshould one or both WSD rotors/stators fail. In this way, either both oronly one can be disengaged from the chopping rotor to allow the farmerto continue to harvest with the combine while operating the chopper andspreader allowing the WSD to be repaired later.

The weed seed destructor section can be of many different types.Examples can include:

-   the arrangements shown and described herein;-   US 8152610 (Assignee: GRDC | Inventor: Harrington | 2008) details a    large and heavy weed seed destructor mill which is mounted on a    mobile frame, powered by a separate engine and is pulled behind a    combine harvester. The mill is made with two counter rotating    rotors. Chaff and weed seeds are collected from the combines sieves    and blown from the harvester to trailing unit. The chaff and weed    seeds enter the center of the rotating rotors and pass through the    multiple counter rotating rings causing damage and devitalization to    any seeds in the chaff. The residue is then spread out behind the    trailed unit.

WO 2014/127408 (Applicant: GRDC | Inventors: Berry/Saunders | 2014)disclosures a further development that was made following the GRDCmachine discussed above. However, unlike the machine discussed above, itdiscloses a weed seed destructor unit which is mounted on the combineharvester behind the sieves. The weed seed destructor mill has acircular array of stationary bars positioned at an angle to the rotationof a rotor, such that there are blunt hits (i.e. impacts) to deflectseeds back into the rotation of the rotor while the seeds and the chaffpass through the destructor. The residue passes through multiple ringsof stationary and rotating bars which inflict damage on any seeds in thechaff. The residue is then spread out to the sides of the harvester.

AU 2016/903873 (Applicant: Seed Terminator Holdings | Inventor: Berry |2016) discloses a multistage hammer mill. Like the above it is mountedon the combine harvester behind the sieves. Rather than multiple ringsof a circular array of stationary bars positioned at an angle to therotation of a rotor it incorporates multiple rings of screens. Like ahammer mill, the rotor grinds, shears and impacts any seed in the chaffuntil it can pass through the screen aperture. The residue passesthrough multiple rings of stationary screens and rotating bars whichinflict damage on any seeds in the chaff. The residue is then spread outto the sides of the harvester.

AU 2016/050802 (applicant: Tecfarm | Inventor: Lewis | 2016) disclosestwo parallel rotors with blunt flails radially extending on each rotor.It is shown that the effective tip diameter of the blunt flails areclose to or intersecting each other. The rotors turn in opposingdirections such that the tip velocity causes impact and devitalizationof seeds in the chaff. The patent discloses the seed destruction deviceon a separate trailed unit however it is known that Tecfarm has mountedthis type of destructor mill on a combine harvester at the rear end ofthe sieves.

The disclosure of each of the above cited patent documents may bereferenced for further detail. The concept herein can be used in anyweed seed destructor design which uses a rotating body. In some casesthe rotating body cooperates with a stator. The stator can include barswhich deflect the seeds as they pass between the bars. The stator caninclude surrounding surfaces which cause the seeds to bounce back intothe path of the rotor. In some cases the rotating body cooperates withanother rotating body.

The arrangement described herein can provide one or more of thefollowing advantages:

-   to provide an improved construction of a weed seed destructor which    provides a simple and efficient construction at lower cost.-   the reduction of operating power,-   an increase in spreading efficiency,-   reduced spatial requirement on the combine harvester,-   additional foreign object protection for the weed seed destructor.    The housing for the auger flighting can be designed so that the    bottom of the housing is not tight to the auger flighting. The high    speed of the auger flighting will drive any heavy objects - rocks or    metal - into the void ( or rock trap) allowing the auger to only    move the lighter chaff.

Preferably at least one of the first and second surfaces is mounted onsaid rotor shaft for rotation therewith. That is the destructor sectionis in effect driven by the rotor shaft in that, where the destructorcomprises a rotor and a stator, the rotor can be mounted on the shaftfor rotation therewith while the stator surrounds the rotor.

Preferably there is provided a transfer system to move the secondmaterial from the second location to the weed seed destructor section.

In one example, the destructor could comprise two rotors where one rotoris mounted on the shaft as defined herein and another one rotor can bemounted on a shaft of the transfer system. That is a destructor rotorcan be mounted on each end of the transfer device with each discharginginto a destructor rotor mounted on rotor as defined herein which can bethe rotor of the straw chopper.

Preferably the transfer system comprises at least one duct and a blowerarrangement for blowing the second material along the duct.

Alternately the transfer system could comprise at least one duct with ascrew or paddle conveyor.

Preferably the rotor shaft and the transfer system are driven by a beltfor receiving drive from an output shaft of the combine harvester.Alternatively, as the transfer system does not consume a lot of power,it could be driven by hydraulics which can therefore easily be turned onand off.

Preferably the drive system incorporates a method to decouple thetransfer system to reduce power when not required.

Preferably there is a common drive from the combine harvester to thechopper rotor of the straw chopper section and the shaft of saidtransfer system.

Preferably the transfer system is driven from the rotor shaft.

Preferably the transfer system comprises an intake in front of a housingof the rotor.

Preferably the system includes a method to allow the second material tobypass the transfer system when not required.

Preferably the transfer system comprises a housing which is connected tothe housing of the rotor.

Preferably the transfer system housing is mounted to the housing of therotor.

Preferably the transfer system comprises an auger flight arrangement formoving the second material outwardly to at least one side of the combineharvester to said blower arrangement and duct to convey the secondmaterial to the rotor seed destruction section. Alternately the transfersystem could be a conveyor belt, air flow conveyor or contain individualpaddles on the shaft to urge the material to the chopper rotor.

Preferably the auger flight of said transfer system is mounted on ashaft which drives the blower arrangement.

Preferably the auger flight is arranged to move the second material toeach side of the combine harvester and wherein there is provided ablower arrangement at each side.

Preferably the blower arrangement is located outside the end of therotor housing and duct extends outside an end wall of a housing of therotor.

Preferably the rotor shaft carries a plurality of straw engaging membersfor engaging the straw.

Preferably the destructor section is located at a position on the rotorshaft axially separated from the straw engaging members.

Preferably the destructor section is located at a respective end of therotor shaft.

Preferably the weed seed destructor comprises a first weed seeddestructor section at a first end of the rotor shaft and a second weedseed destructor section at a second end of the rotor shaft.

Preferably the weed seed destructor includes a common discharge with thefirst material.

Preferably the at least one weed seed destructor is arranged to expelthe second material into a secondary spreading device.

Preferably the secondary spreading device comprises a tailboard with aplurality of fins.

Alternately the secondary spreading device could include poweredspreading discs.

The shaft can comprise any one of the shafts of the combine harvester sothat in one arrangement the rotor is a rear straw chopper; in anotherarrangement the rotor is an internal straw chopper; in anotherarrangement the rotor is an internal beater and in yet anotherarrangement the rotor is a dedicated shaft for the seed destructor only.

Preferably the weed seed destructor comprises at least one cutting bladeand at least fan blade in the inlet for cutting material other thanchaff in the second material.

Preferably the fan blade creates enough airflow to spread both the firstand second material.

Alternatively, additional fan blades can be attached to the straw sideof the seed destructor rotor to provide additional airflow.

Alternatively, additional fan blades or blades with a larger effectivefrontal width than the leading edge can be mounted to the rotor toincrease airflow.

Preferably the airflow accelerates both materials into the secondaryspreading device. Preferably the stator or stators comprises a pluralityof stator bars at angularly spaced positions around the axis of therotor;

-   each stator bar extending axially along the axis of the rotor and    being spaced from a next adjacent stator bar to provide an axially    extending space therebetween through which weed seeds can pass;-   each stator bar comprising an elongate member which is L-shaped in    cross-section to define a first leg lying in a cylindrical surface    surrounding the axis of the rotor and a second leg extending    outwardly from the cylindrical surface connected to the first leg at    an apex at a leading end of the first leg relative to the direction    of rotation of the rotor.

Preferably the apex is smoothly curved at the junction between the firstleg and the second leg so it defines a radius of curvature where theradius of curvature can lie in the range 5 to 10 mm.

As an alternative, the apex is not smoothly curved but instead includesa portion of the surface which is at an inclined angle relative to thefirst leg so as to tend to reflect the weed seeds when impacting thereonat an inclined angle back toward the rotor. That is both the smoothlycurved apex and the inclined portion provide a portion of the surfacewhere the seeds which move outwardly from the edge of the rotor bladesare reflected back into the rotor for further impacts to be generated.It will be appreciated that the seeds tend to rebound from a surfacegenerally at an angle of rebound which is equal to an angle of impact sothat a surface at 45 degrees to the first leg will tend to rebound theseeds back into the rotor rather than tangentially of the rotor.

Preferably the second leg extends outwardly from the apex to define aportion thereof beyond an outer end of the apex. In this way theformation of the stator bar can be obtained very easily by bending asheet metal strip along a center line forms two legs where the firstlies in the cylindrical surface and the second extends outwardlytypically at right angles to the first. However the legs may be ofdifferent lengths with particularly the second leg being very short orhardly existent.

Preferably the second leg lies at an angle to the first leg which is atright angles to the first leg. However the second leg can be bentthrough more than 90 degrees so that it is at an angle to the first legwhich is less than right angles to the first leg. This forms the apexportion into a smooth part cylindrical body wrapped around from thefirst leg to the second leg. It will be appreciated that the impactsfrom the seeds on the stator bars occur over those parts facing inwardlyinto the rotor including the first leg and the apex portion. Impacts onthe second leg do not interfere with the path of the seeds as they arealready moving outwardly from the stator.

Alternately the second leg can be bent at an angle less than 90 degreesso that the angle between the first and second leg is greater than 90degrees. In this case all impact surfaces will tend to reflect the seedback to the rotor creating a higher devitalization rate with higherpower requirements.

Typically the stator bars lie in a line parallel to the axis so that theapexes are directly parallel to the rotor axis. However the stator barscan be inclined to the line parallel to the axis at the cylindricalsurface so that they are all tilted to the left or right. Where the barsare parallel to the axis, typically the second legs lies in an axialplane of the axis of the rotor.

Preferably the width of the first leg in the cylindrical surface is inthe range 10 to 20 mm. Preferably the spacing between each bar and thenext at the cylindrical surface lies in the range 10 to 50 mm. The widthof the first legs relative to the spacing between the trailing edge ofeach bar and the apex of the next controls the amount of material whichis allowed to escape between the bars. Increasing the length of the legsand/or decreasing the spaces increases the amount of material whichremains inside the stator and thus increases the number of impacts andthe power requirement for moving the material. Conversely the power canbe reduced by increasing the proportion of space to leg but withconsequent reduction in impacts and hence reduction in seed destruction.These ratios can be selected depending on the amount and type of seedsto be treated.

While the dimensions of the second leg in the outward direction havelittle effect on the operation, typically the width of the second leg inthe outward direction is in the range 10 to 20 mm.

Preferably the outer edge of each of the second legs lies in a commonimaginary cylinder surrounding said cylindrical surface as this makesthe manufacture of symmetrical stator bars by bending sheet metal stripsa more effective method.

Preferably the stator bars extend along a full height of rotor so thatthe height of the stator matches that of the rotor. However stators canbe stacked one on top of another where the rotor is of increased height.

Preferably the first and second legs of the stator bar comprise portionswhich are flat as this allows a simple bending of a flat strip to formthe bars.

Preferably each of the stator bars comprises a sheet metal plate whichis bent to form the two legs. However other materials and methods ofmanufacture can be used.

Preferably the stator construction includes a stator support member anda plurality of angularly spaced stator portions mounted on the supportmember where the stator support member is cylindrical so as to surroundthe axis of the rotor and the stator portions are part cylindrical witheach of the plurality of stator portions extending around a part only ofthe periphery of the support member. Each such portion includes aplurality of the stator bars.

In this arrangement preferably there is provided a discharge openingbetween each stator portion and the next.

This construction of separate replaceable stator portions allows aplurality of the stator portions to be provided having differentcharacteristics which can be selected for different weed seed sizes andamounts. The selection of the portion also can be used to change powerrequirements.

In particular, the different characteristics or the portions to the usedin any circumstance relate to the length of the first leg of the statorbars around the axis and/or the spacing between the stator bars aroundthe axis.

This construction of part cylindrical stator portions allows theportions to be hard surface coated as a separate component from thesupport member. To provide an effective mounting of the separateportions, preferably each of the stator portions comprises mountingedges at angularly spaced ends of the portion for attachment to a railof the support member. This can be used with a support structure whichcomprises a top and bottom ring around the axis of the rotor with aplurality of rails parallel to the rotor axis.

In some cases the stator includes a plurality of discharge openings atangularly spaced positions around the stator with the support memberbeing angularly adjustable around the rotor axis to move the openings.

In most cases there is provided inner and outer coaxial cylindricalstators where preferably at least one of inner and outer stators isadjustable to change the angular relationship therebetween. Preferablythe angular position of at least one of the stators is adjustable by acontrol linkage from a cab of the combine harvester.

Preferably there are provided rotor components between the inner andouter stators.

Preferably the rotor comprises a hub carrying rotor blades defining saidrotor surfaces where the blades are pivotally mounted about an axisparallel to the rotor axis so as to act as flails.

Preferably the rotor comprises a plurality of blades where an outersurface of each blade has a leading edge which is closest to thecylindrical surface and tapers away from the cylindrical surface towarda trailing edge.

The arrangement herein thus in one example provides three stator ringswhere on the outer ring there are six stator inserts. Some or all of theinserts have an additional release opening, in addition to the spacesbetween the stator bars to allow material in the impact mill the abilityto escape from inside the stator to the next stage, thus reducinghorsepower. The openings can be located within the stator insert or canbe located between each insert and the next.

The middle ring has five inserts so as to define a larger gap betweenthe stator bars. The inner ring has four inserts so as to form a yetlarger gap between the stator bars. All the stator bars in each of theinserts have the same profile, formed for example with a 7 mm leadingradius and 20 mm legs at 90 degrees apart. The apex is preferablesmoothly curved without a sharp intersection between the legs since asharp point would risk material hanging up on the edge which would actto increase power requirements.

The user can set a predetermined balance between the seed kill rate andpower requirements, both of which are dependent on the number of impactsand thus the ratio of the openings to bars in the stator.

Thus all rings can incorporate larger spaces or additional releaseopenings as are provided on the outer ring. If there is a reason toincrease the kill rate on a small weed seed, this ratio of opening areato impact area can be adjusted by selecting bars where the first ortangential legs are increased in length or by reducing the gaps betweenthe stator bars and/or eliminating or reducing the additional releaseopenings on the outer ring to increase the time the weed seed spendsbeing impacted in the mill.

According to another feature which can be used herein there is providedan apparatus for destroying weed seeds comprising:

-   a housing arranged to be mounted at a location on a combine    harvester for receiving a feed material containing separated chaff    and weed seeds separated by the combine harvester from harvested    crop;-   a rotor mounted in the housing for rotation in a direction of    rotation about a rotor axis, the rotor including rotor surfaces    thereon for engaging the feed material and for accelerating the feed    material in a direction outwardly from the axis of the rotor;-   at least one stator arranged at a location outwardly of the axis for    engaging the weed seeds in the accelerated feed material;-   said at least one stator comprising a plurality of stator bars at    angularly spaced positions around the axis of the rotor;-   each stator bar comprising an elongate member extending axially    along the axis of the rotor and being spaced from a next adjacent    stator bar to provide an axially extending space therebetween    through which weed seeds can pass;-   wherein at least one stator bar comprises a first surface tangential    to the rotor axis joined to a curved apex surface joined to a second    surface extending generally outwardly from the rotor axis.

Preferably the second surface of the stator bar is substantiallyperpendicular to the tangential surface.

Preferably the first and second surfaces of the stator bar aresubstantially flat.

Preferably the first surface of the stator bar has a length in thetangential direction which is greater than 10 mm.

Preferably the first surface of the stator bar has a length in thetangential direction which is at least equal to a length of the secondsurface in the radial direction.

Preferably the first surface has a length of the stator bar in thetangential direction which is at least equal to the spacing between thebars in the tangential direction.

Preferably the spacing between the bars in the tangential direction isat least equal to the length of the second surface in the radialdirection.

Preferably the spacing between two of the bars in the tangentialdirection is greater than the spacing between others of the bars.

According to another object of the invention there is provided a combineharvester comprising:

-   a separation system for separating from harvested crop at a first    discharge location a first material comprising straw and at a second    discharge location a second material comprising chaff and weed    seeds;-   a rotor mounted on the combine harvester at a location thereon to    engage the first material, the rotor including a rotor shaft;-   at least one weed seed destructor section comprising:    -   rotor surfaces arranged for rotation about an axis to engage the        second material for accelerating the second material in a        direction outwardly from the axis;    -   at least one other surface arranged for engaging the accelerated        second material such that the accelerated second material is        impacted between said rotor surfaces and said at least one        other;    -   said rotor surfaces being mounted on said rotor shaft for        rotation therewith.

Preferably there is provided a transfer system to move the secondmaterial from the second location to the weed seed destructor section.

According to another object of the invention there is provided a combineharvester comprising:

-   a separation system for separating from harvested crop at a first    discharge location a first material comprising straw and at a second    discharge location a second material comprising chaff and weed    seeds;-   a rotor mounted on the combine harvester at a location thereon to    engage the first material, the rotor including a rotor shaft;-   at least one weed seed destructor section comprising:    -   rotor surfaces arranged for rotation about an axis to engage the        second material for accelerating the second material in a        direction outwardly from the axis;    -   said rotor surfaces being mounted on said rotor shaft for        rotation therewith.

Preferably there is provided a transfer system to move the secondmaterial from the second location to the weed seed destructor section

at least one other surface arranged on the transfer device for engagingthe accelerated second material such that the accelerated secondmaterial is impacted between said rotor surfaces and said at least oneother

BRIEF DESCRIPTION OF THE DRAWINGS

One embodiment of the invention will now be described in conjunctionwith the accompanying drawings in which:

FIG. 1 is a side elevational view of an apparatus for destruction ofweed seeds according to the present invention which is arranged in afirst embodiment where a rotary mill section is mounted at a position ona combine harvester on a rotary shaft of the conventional straw chopperlocated in the path of the straw.

FIG. 2 is an isometric view of the apparatus for destruction of weedseeds of FIG. 1 which shows the location of the rotary mill.

FIG. 2A is a top plan view of the shaft and rotary mills of FIGS. 1 and2 .

FIG. 3 is an isometric partly exploded view of a part of the shaft andone rotary mill of FIGS. 2 and 2A.

FIG. 4 is an isometric view of the collection and conveying system whichcarries the chaff and weed seeds from the rear of the sieve to therotary mills.

FIG. 5 is a side elevational view of an apparatus for destruction ofweed seeds according to the present invention which is arranged in asecond embodiment where a rotary mill section is mounted at a positionon a combine harvester on a rotary shaft of the conventional strawdischarge beater located in the internal area of the combine.

FIG. 6 is a side elevational view of an apparatus for destruction ofweed seeds according to the present invention which is arranged in athird embodiment where a rotary mill section is mounted at a position ona combine harvester on a rotary shaft of the conventional internal strawchopper used on some combine harvesters located in the internal area ofthe combine in the path of the straw.

FIG. 7 is an end elevational view of one weed destructor mill of theembodiment of FIGS. 1 to 6 .

FIG. 8 is an exploded view of the mill of FIG. 7 .

FIG. 9 is a plan view of one stator element of the outer ring of therotor of the embodiment of FIG. 4 .

FIG. 10 is a plan view of one stator element of the inner ring of therotor of the embodiment of FIG. 4 .

FIG. 11 is a plan view of one stator element of the inner ring of therotor of the embodiment of FIG. 4 showing a first alternative shape forthe stator bars.

FIG. 12 is a plan view of one stator element of the inner ring of therotor of the embodiment of FIG. 4 showing a second alternative shape forthe stator bars.

FIG. 13 is an isometric view of a combination chopper rotor and weedseed destructor rotor similar to that shown in FIG. 3 for use in theembodiment according to the present invention as shown in FIG. 1 .

FIG. 14 is an exploded view of the combination chopper rotor and weedseed destructor rotor of FIG. 13 .

FIG. 15 is an isometric view partly exploded of the weed seed destructorrotor of FIG. 13 .

FIG. 16 is an isometric view of the inner portion of the weed seeddestructor rotor of FIG. 13 .

In the drawings like characters of reference indicate correspondingparts in the different figures.

DETAILED DESCRIPTION

The apparatus herein is shown in FIG. 1 mounted on a combine harvestercarried on ground wheels and including harvesting components of aconventional nature. This can include in some current embodiments aconventional separator with straw walkers with a threshing cylinder axisperpendicular to the direction of travel, in other embodiments using anaxial separator with a rotor axis aligned with the direction of traveland in other embodiments using aligned threshing rotors perpendicular tothe direction of travel. Other arrangements are also possible.

In most embodiments, the rearmost part of the separation system is thesieve which allows passage through of harvested seeds for collection anddischarges chaff and discarded seeds including weed seeds to the rearedge of the sieve.

Thus the separation system including the threshing system and thecleaning system defined by the sieves operates for separating harvestedcrop into a first material comprising straw and a second materialcomprising chaff and weed seeds.

The combine harvester shown in FIG. 1 includes a separating rotor at thelocation 100 feeding the straw onto a beater or straw chopper rotor 101which completes a further and final separation before the first materialcontaining the straw is discharged from the separation system atlocation 102 into a straw path 103 for passage to a discharge from thecombine harvester.

The combine harvester as shown includes a chopper and dischargearrangement 9 shown in FIGS. 1 and 6 is basically as shown in US Pat.6840854 issued Jan. 11, 2005 of Redekop, the disclosure of which may bereferenced for further detail. The chopper thus comprises a housing 10defined by a top wall 11, a bottom wall 12 and two end walls 13. The endwalls 13 include attachment means 13A for attachment of the housing 10to the outlet 104 of a combine harvester for discharge of straw andoptionally chaff from the combine harvester into an inlet opening 15 ofthe housing 10. The bottom wall 12 defines a semi-cylindrical portionextending from the inlet 15 to an outlet 16 through which chopped strawand air is discharged at relatively high velocity for spreading acrossthe field in a wide spread pattern.

Within the housing is mounted a hub 17 including a shaft 17A which iscarried on suitable bearings for rotation about a hub axis 18 at acenter of the housing. The shaft can form a complete shaft body acrossthe full width or it may be formed from stub shaft portions attached tothe hub 17 at each end. Blade members 19 carried by the hub 17 sweeparound within the housing to entrap straw fed through the inlet 15 andto carry the straw and air past stationary blades 10A for chopping andfor discharge through the outlet 16. The stationary blades are mountedon the housing at a position approximately midway between the inlet 15and the outlet 16 so that blade members 19 carried on the hub sweepbetween the stationary blades in a cutting action.

In this arrangement of the chopper, there are provided three axiallyspaced sections of the chopper assembly including a first fan section 30at one end of the hub 17 and a second fan section 30 at the other end ofthe hub 17. In-between the two narrow fan sections 30 is defined acenter section 30A which provides the whole of the cutting action.

The chopper and spreading assembly 9 is arranged to be mounted at a rearstraw discharge of the combine harvester and includes the housing 10,the rotor 17 mounted in the housing 10 for rotation around a generallyhorizontal axis and carrying the plurality of chopper blades 19 forchopping the discharge material.

At the exit 16 is provided the material spreading assembly which can bethe form of a tailboard 16A with guide fins 16B for receiving thechopped material and spreading the material to the rear and sides of thecombine harvester.

In this embodiment a seed destructor is provided which includes twoseparate destructor elements 38, 39 positioned in this embodiment on theshaft 17A of the hub 17 at the ends where the fan sections 30 arelocated. Each element 38, 39 as best shown in FIG. 7 comprises housing36 with base 37 at or defined by the end wall 13 of the housing 10. Thebase 37 and a generally cylindrical outer surface 37A are covered by acover panel 42. The cover panel (as shown in FIG. 8 ) is held stationaryand includes a central circular inlet 43 for feeding the second materialfrom the sieve containing the chaff and weed seeds onto a rotor 44mounted on the shaft 17A of the hub 17. Around the shaft 17A is provideda plurality of pivot pins or bolts 46 each carrying a pair of flailblades 47. The flail blades extend from an inner end with a plurality offingers extending into connection to the pin 46. An outer end of theflail blade 45 broadens in the axial direction of the axis 18 of the huband terminates in an edge 48 lying in an imaginary cylindrical surfacesurrounding the axis. The flails can retract inwardly by pivotalmovement in the event of impact with a larger object. Thus the blades 47are pivotally mounted about an axis parallel to the rotor axis so as toact as flails. Also each of the rotor blades include a sharpened cuttingedge 49 radial to the axis and a fan blade portion 50 generally axial ofthe axis. The fan blades 50 of the mill act to generate a significantair flow through the mill to the outlet 200 of the mill. The outlet 200directs the outlet air onto the tailboard 16 and the fins thereon tosupplement the stream of air and straw from the blades 19. In this waythe mills act in the same manner as the fan blade sections shown in theabove cited US Pat. 6840854 of Redekop. It will be appreciated thereforethat the addition of the stator portions of the mill to the fan endsections of the straw chopper rotor enable the straw chopper to carryout both functions of straw chopping and milling the chaff together withthe spreading of both materials. This provides a system of highefficiency with low numbers of moving parts to enable the constructionof a device at lower cost.

Around the rotor is provided a stator 500 formed by a number ofstationary annular coaxial cylinders 51 and 52 and optionally 501 withcylinder 51 inside the cylinder 52. The stator cylinders are carried onthe stationary end wall 37 so that they project into the rotor 44. Thecover forces the weed seeds to contact the stator 500 and rotor 44 to beimpacted thereby thus devitalizing the seed.

Each stator cylinder is of the construction shown in FIGS. 7 and 8 andincludes a top flange 53, a bottom ring 54 parallel to the flange and aplurality of upstanding connecting posts or bars 55 to form a rigidstructure.

The stator cylinder 51, 52 can optionally be formed from a plurality ofinserts 56 closing the space between the flange 53 and the bottom ring54. Each insert forms a part cylindrical surface which extends aroundthe axis by a limited angle. As shown in FIG. 8 there are six suchinserts each covering an angle of the order of 60 degrees so that theplurality of inserts cooperate to partly surround the axis. The insertsmay be manufactured with different numbers and widths of stator bars soas to be made with larger openings between the stator bars. Thecombination of inserts can be selected to increase or decrease thenumber of openings or additional release points.

Each insert 56 has a plurality of the stator bars 55 parallel to therotor axis. Different constructions of inserts can be provided withdifferent numbers and dimensions of bars to provide a different grindingor impacting effect on the material in engagement with the inserts. Theinserts are shaped with an angled edge flange 58 which is shaped toengage against a side edge of a suitably shaped one of the rails 55.Thus as shown in FIG. 8 , the ends 58 of the plates 56 engage againstsides of the bars 55. In FIG. 8 , three types of inserts are shown, ofwhich many more styles could be envisioned, which can be selected foruse in the base frame of FIG. 7 .

In operation, the rotor flails 47 act to suck chaff and weed seed intothe mills through the inlet opening 43 in the cover 42 and accelerateand direct the material across the inside surface of the inner statorring 51 to impact, shear and force some of the material through thespaces between the bars 55. The outer edge 48 of the flail blade thusacts to wipe the material cross the inside surface of the selectedinsert with the edge 48 having a height substantially matching theheight of the insert 56.

That material which does not escape through the spaces between the bars55 is carried around the inner surface of the insert 56 to the next oneof a plurality of discharge slots or spaces between the bars 55. Thematerial sliding on the inner surface thus can escape through the innerstator ring 51 to the next outer annular stator 52. Between the twostators 51, 52 is an annular rotor 60 defined by ring of posts 601 whichare attached to a base plate of the rotor so as to rotate with the shaft17A of the center hub 17 and with the flail blades 47 attached to theshaft. These posts 601 act to impact, accelerate and shear the materialround the inside surface of the outer stator 52. The arrangement canalso include a third stator 501 coaxially surrounding the stator 52 witha further rotor 62 of a similar structure to rotor 60 between thestators 52 and 501.

The stator 501 has the same structure as the stators 51 and 52 but ofincreased diameter. Again there is a plurality of separate inserts 56 atangularly spaced positions. The outer stator therefore operates in thesame manner under the rotation impetus on the material from the posts ofthe rotor 62 to impact and shear the material and then to allow anyremaining material remaining on the inner surface of the outer stator toescape outwardly. The material escaping is flung outwardly and angularlyagainst the outer surface 40.

Each stator which is in the form of a ring or cylinder supported fromthe top cover and located between the components of the rotor is thusformed from the fixed base frame shown in FIG. 7 with a plurality oflocations each for mounting a respective one of the stator insertcomponents with an outlet opening between each plate or between eachstator bar of the plate and the next. As shown in FIG. 8 , differentforms of the stator inserts can then be selected for use with the frameof FIG. 7 and installed and replaced as required. The stators can alsobe formed from annular components fully surrounding the axis without theindividual part cylindrical inserts of FIG. 8 .

The use of separate stator inserts provides replaceable statorcomponents which have a number of advantages which include:

-   a- simple service, it is possible to replace and discard small parts    of the stator rather than the entire stator ring.-   b- customer cost, the arrangement provides lower cost service parts,    longer lasting parts with the possibility that the smaller parts of    the components alone can be made harder.-   c- manufacturing advantage, the components individually are lower    cost, higher volume of a smaller part allowing economy of scale to    provide lower cost manufacturing.-   d- material, the manufacture of a smaller part allows the use of a    higher value material for that part while the frame itself can be    manufactured from other materials. This allows less material to be    used, allows for harder or heat treatable material to be used for    the wear surfaces of the replaceable stator components while softer,    more ductile or weldable material can be used in the frame. In    particular the stator components or inserts form small parts which    are suitable for hard surfacing or carbide coating processes to    provide increased hardness and wear resistance.-   e- Stator selection; this allows for different stator profiles, that    is different shapes and arrangements of holes, to be selectable to    best match to typical weed seed targets in each farming region. That    is different regions in the world have different weed problems, so    that the system of the present invention allows use of a common    support frame and different wear inserts to best target the efficacy    of the desired weed seed in that region.-   f- Stator Style; the system can provide different styles of stator    inserts to cover different manufacturers particular design of the    stator.

The stator bars 57 of the replaceable stator inserts 56 may be hardsurface coated with a suitable material such as carbide which reducesimpact damage. One or all stators 51, 52 and 501 defined by the annularframe and the supported stator components can be adjusted by rotationaround the axis of the rotor so as to move the position of the openingsbetween the plates. This acts to change the distance that the materialmust traverse before it reaches the escape slot, or a position where thestator bars are spaced a greater distance apart.

The angular position of the stators 51 and 52 is adjustable around theaxis 17A of the hub to move the openings angularly. If the openings ofthe inner stator are located at an angular portions so that they arealigned with the openings of the outer stator then any material exitingthe openings of the inner stator will typically escape from the secondstator by direct radial movement through both openings simultaneouslythus minimizing any processing by the outer stator. Movement of one orboth of the stators so that the openings are not aligned will increasethe effective processing by the second outer stator. It will beappreciated that this processing can be adjusted from a position ofminimum processing where the opening are aligned to a position ofmaximum processing where each opening in the inner stator dischargesonto the outer stator at a distance which is at the beginning of theadjacent stator component so that the material must traverse the wholesurface of the component before reaching the next opening in the outerstator. The actuators are operated by a control where the control is inthe cab for on-the-go control of the position of the stators.

It will be appreciated that the weed destructor herein uses asignificant amount of power to drive when empty and an increased amountwhen filled with the crop materials. This power can be minimized bybypassing the device as described herein and by disconnecting the drivethereto when no treatment of the crop materials is required. Couplingsbetween the rotor shaft 17A and the seed destruction rotors aredecoupled to allow only the rotor to turn. Alternatively, if the seeddestruction rotors are not decoupled the power can be reduced as aboveby moving the stators to the most effective position with minimum croptreatment.

Thus the system herein provides adjustability of stator positions on thego, the advantages of which include:

-   a- Setting the stator contact surface to produce the best efficacy    rate to match weed problems in field while reducing power    requirements.-   b- Reducing power by reducing stator contact time of the crop    material. This is a significant advantage includes which allows    increased combine harvest capacity as current destructor systems are    reducing a farmer’s threshing capacity by up to 30% as well as    reduced fuel consumption.-   c- Manual Adjustment on the go by In Cab control of an actuator    allows the operator to change as they enter visible weed problem    areas in the field. The actuator drives relative position of the    stator rings to change the number of impact surfaces a seed    encounters as it passes through the mill.-   d- Automatic Adjustment on the go allows an operator to develop a    GPS map of a weed problem by aerial surveillance or when mid-season    spraying. This information can be used to adjust the stator    positions for maximum seed efficacy using maximum power in that area    and reduce contact surface after the combine passes through the weed    area.

In an alternate arrangement, in least one stage, the weed seeds do notpass through the stator but are rebounded between the rotor and thestator. The rotor also propels the weed seed from the housing withoutneeding to pass through an outside stator surface so that a higher exitvelocity is obtained.

The arrangement herein thus provides at least one stator 51 comprising aplurality of stator inserts 66 including the stator bars 57 at angularlyspaced positions around the axis of the rotor. The inserts 66 includebottom and top rails 67 and 68 and end support posts 69 and 70 forming arectangular rigid structure with the bars 57 welded to the rings 67 and68 so as to extend at right angles thereto leaving spaces 71 betweeneach bar and the next and between the endmost bars and the posts 69 and70. Each stator bar thus extends axially along the axis of the rotor andbeing spaced from a next adjacent stator bar to provide an axiallyextending space 71 therebetween through which weed seeds can pass.

Each stator bar 55 comprises an elongate member which includes threeimpact surfaces which can be varied in size and length to vary thenumber of impacts a weed seed encounters as it passes through each stageof the mill. The stator bar is preferably L-shaped in cross-section todefine a first leg 571 lying in a cylindrical surface 73 surrounding theaxis of the rotor and a second leg 572 extending outwardly from thecylindrical surface connected to the first leg at an apex 573 at aleading end of the first leg relative to the direction D of rotation ofthe rotor.

The arrangement herein thus provides a stator bar which includes atangential surface, an apex at a leading edge of the tangential surfaceand a third surface which is generally radial whereas previousarrangements typically before have had either a tangential or radial orapex, but not all three and thus provides an advantage over, anddifferentiator from, the prior art, enabling higher weed seeddevitalization rates at lower power requirements.

The stator bar is preferably formed by bending a strip of sheet metalalong a center line or approximately at the center line to form the legs571 and 572 with a smooth curve 573 interconnecting the legs. The apex573 defines a radius of curvature which can lie in the range 5 to 15 mmand more preferably of the order of 7 mm. However the same surfaces canbe formed on the outside of a body which is a solid bar, not a bentstrip or on the outside of a hollow bar.

The apex thus defines a portion 573 of the surface which is at aninclined angle relative to the first leg 571. As shown in FIG. 10 , aseed S is carried along in the direction D1 by the rotation of the rotorblade so that it moves around the axis with some outward movement undercentrifugal force. Some seeds impact the leg 571 on its inner surface.Some seeds pass through the opening 71 between the trailing end 574 ofthe leg 571 and the apex 573 of the next stator bar. These seeds andaccompanying material will escape outwardly from this stator to the nextstator or to the wall or outer surface 40. Some of that material mayengage the radial outwardly extending surface of the leg 572 so as tochange direction but generally any material impacting the bar outside ofthe apex will escape outwardly. Some of the seeds and material willimpact the bar 57 at the apex 573 and hence will tend to reflect theweed seeds when impacting thereon at an inclined angle back toward therotor.

The second leg 572 typically lies in an axial plane of the axis of therotor but in some cases such as that shown in FIG. 12 where the bend inthe strip forming the bar is greater than 90 degrees, the leg 572 may beclose to or even alongside the leg 571. The legs are typically flat asthe only bend in the strip is at the apex.

Alternately the second leg 572 could be bent less than 90 degrees asshown in FIG. 11 so that the angle between the two legs is greater than90 degrees. In this case all three surfaces would tend to reflect theseed back to the rotor and therefore would create more impacts as theseeds pass through the mill but with a greater power requirement.

The width of the first leg in the cylindrical surface 73 as indicated atX3 is in the range 10 to 30 mm and preferably of the order of 20 mm.

The width of the second leg in the outward direction as indicated at X2is in the range 10 to 30 mm and preferably of the order of 20 mm. Thisprovides an arrangement in which all the second legs are of the samelength with the outer edge thereof lying in an imaginary cylinder 74.

The width of the space 71 in the cylindrical surface 73 as indicated atX1 is in the range 10 to 30 mm and preferably of the order of 20 mm.

In order to prevent the outer edge or the blade of the rotor frompinching material against the legs in the cylinder 73, the rotorcomprises a plurality of blades where an outer surface 75 of each bladehas a leading edge 76 which is closest to the cylindrical surface 73 andtapers away from the cylindrical surface toward a trailing edge 77.

In the embodiment of FIGS. 1 to 4 , therefore there is provided acombine harvester including a separation system with a threshing rotor100 and a sieve arrangement 106 for separating from the harvested cropcut by the front header at the first discharge location 103 the firstmaterial comprising straw and at a second discharge location 107 thesecond material including chaff and weed seeds. A transfer surface 108can be provided to carry the second material to the second location 107.

As described above, the combine includes the straw chopper 9 which hasthe hub 17 mounted on a shaft 17A defining a rotor mounted on thecombine harvester the rear discharge on the combine to engage the firstmaterial including the straw.

The rotor or hub 17 as described above includes the chopping blades 19of the conventional straw chopper so that the rotor surfaces are mountedon the rotor shaft 17A and hub 17 for rotation therewith.

In this arrangement the chopper includes two weed seed destructorsections 38, 39 each arranged inside the end wall of the housing at theend section of the rotor. Each of these includes the rotor 44 mountedfor rotation about the axis of the shaft 17A to engage the chaff andweed seeds fed from the location 107 by the arrangement describedhereinafter for accelerating the material in the direction outwardlyfrom the axis to engage the stator 51, 52 arranged around the rotorsurfaces including one or more rotor surfaces 60, 62 for engaging thematerial such that the material and particularly the weed seeds areimpacted between the rotor surfaces and the stator surfaces.

As shown in FIGS. 2 and 4 , there is provided a transfer systemgenerally indicated at 110 to move the second material including theweed seeds from the second location 107 to the weed seed destructorsection defined by the two destructors 38 and 39. The transfer systemcomprises a transverse tubular housing 111 containing an auger flight112 on a shaft 118 separated at the middle so as to carry material fromthe center toward each end as the auger flight rotates.

The housing for the auger flighting is designed so that the bottom ofthe housing is not tight to the auger flighting. The high speed of theauger flighting acts to drive any heavy objects, rocks or metal, intothe void which thus acts as a rock trap allowing the auger to only movethe lighter chaff to the destructors.

At each end of the flight is provided a respective blower 113, 114 in acylindrical housing including fan blades driven by the shaft 117 of theauger. The shaft is driven by a belt drive system from the drive to thechopper 9. The transfer drive system includes a coupler to engage ordisengage the drive to save power when the system is not required to beused. The transfer system also includes a bypass mechanism to allow thesecond material to bypass the system when it is not in use. The transferthus includes at least a blower arrangement 113, 114 for blowing thesecond material along a respective duct 115, 116. The ducts extend alongthe outer face of the housing of the chopper and discharge the secondmaterial through the opening 43 in the end wall 42 (FIG. 8 ) to enterthe middle of the rotor 44 of the destructor 38, 39. An alternativetransfer system could be providing an air blower system which avoids thenecessity for any mechanical movement to blow the material into achopper destructor or an auger system such which uses two auger flightsto move the chaff and weed seeds to the required location without thenecessity for air flow. Many other material transfer systems could beutilized.

That is the rotor shaft 17A and the transfer system including the shaft117 are both driven by a belt for receiving drive from an output shaftof the combine harvester so that there is a common drive from thecombine harvester to the chopper rotor of the straw chopper section andthe shaft 117 of the transfer system. Alternately the low powerrequirement for the transfer device allows the device to be driven by ahydraulic motor to provide the simple command afforded byelectro-hydraulic controls.

It will be noted from FIG. 1 that the transfer system 110 has an intakein front of a housing of the rotor of the chopper 9 with the housing 111being mounted on or as part of the housing of the straw chopper rotor.

Thus the transfer system includes the auger flight arrangement formoving the second material outwardly to one or both sides of the combineharvester to the blower arrangement and duct to convey the secondmaterial to the rotor seed destruction section.

In another embodiment (not shown) the auger may be arranged to carry thesecond material only to one side where a single blower and single ductcan carry the second material to a destructor at one end only of the hub17. In this arrangement the single destructor can be mounted on thechopper shaft 17A or on any other driven shaft within the straw flowpath.

In another embodiment (not shown but based on the embodiment shown inFIG. 1 ) a construction of the type shown in the above cited patentdocument of TecFarm can be provided where one rotor 24 (See numbers inTecFarm Figure) is mounted on the shaft 117 and the second rotor 26 ismounted on the shaft 17 with the housing 12 surrounding the two rotors.Where two such mills are required, one can be mounted at one end of theshafts 17, 117 and the other at the other end with each mill being fedby the auger mounted on the shaft 117.

The arrangement shown is particularly effective in that the destructorsections are mounted in the chopper housing 10 without significantlyincreasing the width of the structure. That is the chopper rotor remainsof the same width as the straw path. Only the blowers 113 and 114 andthe associated ducts 115, 116 are mounted outside the width of thechopper housing. Alternatively, the blowers 113, 114 could be mounted inthe same plane as the destructor rotors 38, 39 so that only the ducts115, 116 are outside the chopper width utilizing a narrow configurationand a small amount of space on the combine harvester.

Also the weed seed destructors 38 and 39 generate an air flow volume andrate somewhat similar to that of the conventional fans of theconventional Redekop chopper (of the type shown in the abovementionedpatent) so that the total volume of air generated and fed onto the tailboard with the combined first and second materials for spreading isequal to or even greater than that of the conventional chopper.

The destructors 38 and 39 are located in the separate sections at theends of the rotor so that they do not interfere with the conventionalstraw chopping action of the rotor.

The weed seed destructors are arranged to expel the second material intoa secondary spreading device. In the embodiment shown this is thetailboard. However other arrangements may use a rotary spreading system.This can be used where the air flow is insufficient to generate therequired spread such as where the straw chopping section is internal tothe combine rather than the dedicated rear chopper shown.

In the embodiment shown in FIGS. 1 to 4 , the rotor is the rear strawchopper so that the transfer system can be mounted in front of thechopper housing. However as shown in FIG. 5 , in an arrangement wherethere is no rear straw chopper, or there is not an efficiency inmounting the weed seed destructor to the rear chopping rotor, the shaftmounting the weed seed destructors can be the shaft 120 of the internaldischarge beater 121 of the combine. Again the destructor can be locatedwith two end annular members 123 on the shaft 120 within the width ofthe combine housing. Also a single destructor 123 can be mounted on theshaft 120 at one end in which case the destructor may be outside thehousing.

In yet another arrangement shown in FIG. 6 the destructor 131 is mountedto the shaft 132 of an internal straw chopper 130. In both these cases,again the second material can be collected by an auger and fanarrangement such as that in FIG. 4 but the ducts extend forwardly to alocation at the respective cross shaft within the combine.

In yet another arrangement the destructor shown in FIG. 6 a destructor131 is mounted to an independent cross shaft 132. In both these cases,again the second material can be collected by a transfer device such asan auger and fan arrangement such as that in FIG. 4 but the ducts extendto the location at the respective cross shaft within the combine.

In yet another arrangement (not shown) a rotor of the destructor ismounted to the shaft 17A and a second rotor surface is mounted on theshaft 118 of the transfer device. The second material can be collectedby a transfer device such as an auger and fan arrangement such as thatin FIG. 4 but the ducts extend to the location at the respective crossshaft within the combine.

Turning now to FIGS. 13 to 16 , as described above, there is provided aweed seed destructor section 90 at each end of the convention chopperrotor 91. The rotor axis 92 of each weed seed destructor section isco-axial with the rotary axis of the rotary member defined by thechopper rotor 91 for common rotation about a common axis defined by theaxis 92.

The rotary member 91 includes a hub 94 carrying the blades 95 where thecylindrical hub 94 is mounted upon or includes a shaft component 96along the common axis 92. The shaft component 96 can form a stub shaftattached at each end of the hub or can pass along the whole chopperrotor. Thus the shaft 96 at each end of the chopper rotor rotatesrelative to bearings (not shown) carried on the housing about the axis92 to drive the blades 95 in the chopping action. The shaft includes apulley (not shown) for applying drive to the chopper rotor to carry outthe chopping action.

As described above, the rotor 90 of the weed seed destructor section ismounted on the shaft component 96 and is connected by connecting screws97 to the chopper rotor for common rotation about the common axis 92.Thus the drive to the shaft also drives the rotor 90 of the WSD.

The end of the hub 94 includes an end plate member 98 lying in a radialplane of the common axis 92 and the rotor 90 is fastened to the platemember 98 by the connecting elements or screws 97.

The connecting elements 97 are readily releasable by unscrewing a nut orthreaded rod to allow the rotor 90 to remain in place on the shaft whileremaining stationary while the chopper rotor continues to rotate aboutthe common axis and carry out its required chopping and spreading actiondriven by the drive pulley.

The rotor 90 is mounted on the shaft component by a center bearing 99 toallow the shaft to rotate with the chopper rotor while the rotor 90remains stationary when the coupling is disconnected. Thus the rotor 90can be disconnected from the drive to the chopper rotor in the eventthat one or both WSD rotors/stators fail. In this way, either both oronly one of the rotors 90 can be disengaged from the chopping rotor toallow the combine harvester to continue to harvest while operating thechopper and spreader, allowing the WSD to be repaired later.

The rotor as described above includes the center flail blades 901 andtwo outer coaxial rings of rotor bars 902 and 903. These are mounted ona back plate 904 to rotate as a common body. The back plate 904 isconnected between a front plate 905 or the rotor and the back plate 98of the hub 94.

The connecting screw fasteners when removed disconnect the plates 905and 904 from the plate 98 allowing the plate 98 on the hub 94 tocontinue to rotate while the rotor of the WSD remains stationary.

The transfer section can be halted and bypassed as described above sothat the chaff and weed seeds are no longer operated upon by the WSD andcan be discharged directly to the ground or carried separately to thespreader, which may bot be ideal. However the halting and disconnectionof the WSD allows the main operation of the combine harvester to collectgrain and to chop and spread straw to continue as required.

Since various modifications can be made in my invention as herein abovedescribed, and many apparently widely different embodiments of same madewithin the spirit and scope of the claims without department from suchspirit and scope, it is intended that all matter contained in theaccompanying specification shall be interpreted as illustrative only andnot in a limiting sense.

1. A combine harvester comprising: a separation system including athreshing system which separates harvested crop into a first materialstream comprising straw and a second material stream comprising chaffand weed seeds; a rotary member mounted on the combine harvester forrotation about a rotary axis; wherein the rotary member carries aplurality of straw engaging members engaging the straw in the firstmaterial stream; and at least one weed seed destructor sectioncomprising: an inlet receiving the chaff and weed seeds in the secondmaterial stream; a first rotor having first rotor surfaces engaging thechaff and weed seeds in the second material stream; the first rotorbeing mounted for rotation about a rotor axis of said at least one weedseed destructor section; second stator surfaces engaging the chaff andweed seeds in the second material stream; the first rotor being mountedso that said rotation of the first rotor relative to the second statorsurfaces causing the chaff and weed seeds to be impacted between saidfirst rotor and second stator surfaces so that the weed seeds in thesecond material are devitalized before being spread onto the ground;wherein the rotor axis of said at least one weed seed destructor sectionis coaxial with the rotary axis of the rotary member for rotation abouta common axis; wherein the rotor of said at least one weed seeddestructor section is connected by one or more connecting elements tothe rotary member for common rotation about the common axis; and whereinsaid one or more connecting elements are releasable to allow the rotorof said at least one weed seed destructor section to remain stationarywhile the rotary member rotates about the common axis.
 2. The combineharvester according to claim 1 wherein the rotary member includes ashaft component along the common axis and wherein the rotor of said atleast one weed seed destructor section is mounted on the shaftcomponent.
 3. The combine harvester according to claim 2 wherein therotor of said at least one weed seed destructor section is mounted onthe shaft component by a bearing to allow the shaft to rotate with therotary member while the rotor of said at least one weed seed destructorsection remains stationary.
 4. The combine harvester according to claim1 wherein the rotary member includes a plate member lying in a radialplane of the common axis at the rotor of said at least one weed seeddestructor section and wherein the rotor of said at least one weed seeddestructor section is fastened to the plate member by said connectingelements.
 5. The combine harvester according to claim 4 wherein theconnecting elements comprise axially extending releasable screwfasteners passing through a portion of the rotor of said at least oneweed seed destructor section into the plate member.
 6. The combineharvester according to claim 1 wherein said at least one weed seeddestructor section is located at a position axially separated from thestraw engaging members.
 7. The combine harvester according to claim 1wherein said at least one weed seed destructor section is located at anend of the rotary member.
 8. The combine harvester according to claim 1wherein said at least one weed seed destructor section comprises a firstweed seed destructor section at a first end of the rotary member and asecond weed seed destructor section at a second end of the rotarymember.
 9. The combine harvester according to claim 1 wherein the rotarymember is a rear straw chopper and carries a plurality of straw choppingblades at axially spaced locations therealong.
 10. The combine harvesteraccording to claim 1 wherein the rotary member is an internal strawchopper and carries a plurality of straw chopping blades at axiallyspaced locations therealong.
 11. The combine harvester according toclaim 1 wherein the rotor of said at least one weed seed destructorsection includes an inner rotor component and at least one coaxialsurrounding ring of rotor components and wherein the stator surfacescomprise at least one coaxial ring of stator surfaces located betweenthe inner rotor components and the ring.
 12. The combine harvesteraccording to claim 1 wherein said at least one weed seed destructorsection includes a common discharge with a discharge for the firstmaterial.
 13. The combine harvester according to claim 1 wherein said atleast one weed seed destructor section is arranged to expel the secondmaterial into a secondary spreading device.
 14. The combine harvesteraccording to claim 13 wherein the secondary spreading device comprises atailboard with a plurality of fins.
 15. The combine harvester accordingto claim 1 wherein there is provided a transfer system to move thesecond material from a discharge location to said at least one weed seeddestructor section wherein the rotary member and the transfer system aredriven by a common drive system and wherein the transfer system drivecan be decoupled from the common drive.
 16. The combine harvesteraccording to claim 15 wherein there is provided a bypass by which thesecond material can bypass the transfer system.